GMS 2.3+ [Partially solved] Issue with updating sequence value


Hi guys,

Here's the error:

action number 1
of Create Event
for object <undefined>:

Unable to find any instance for object index '0' name '__YYInternalObject__0'
at gml_Script_scr_rollback (line 6) - seq_title.headPosition = 6;
So my best guess is that for some reason I need an object ?

Just some info:
project has 1 room, 1 sequence, 1 sprite and 1 script which has a function which is where the error occurs.
At a certain point a 'moment' is triggered in the sequence that runs the script which just does "seq_title.headPosition = 6;"

What am I missing ?


I found that there are elements as well, what on earth ?
And so now I've replaced the code with "layer_sequence_headpos(seq_title,6);"
how ever seq_title is still just the sequence object ID? and not the element ID ?
is an element an instance of an object ? or just data of an object to be used in the layer structure ?

Also how on earth do I get the sequence ID ?

What happens if I create a sequence instance programmatically, then ive the sequence instance ID, what's the point of there being duplicates.. it feels like elements and instances is duplicate code.


So having replaced the code as seen in the previous edit it appears to be working, but in this exercise I've found that there's other issues that aren't immediately game breaking, I used the sequence object reference id instead of a sequence elements ID or a sequence instances ID if I've got multiple sequences of the objects then they're all going to be effected due to the reference scope..

But I'll create a new thread for that.
Last edited:


// Auto-generated stubs for each available event.

function rollback()

Nope script is fine.

But if you check out the nested spoiler I mentioned that it's working now, issue now is that I'm not sure how layers elements work and why they exist.